Solution - Determination of Residual Ethylene Oxide and Chloroethanol in Medical Devices by Gas Chromatography

Introduction:

Ethylene oxide (EO) is a flammable gas that can stimulate the body surface and cause strong reactions. In many cases, ethylene oxide has mutagenic, fetal toxic, and teratogenic properties, which have adverse effects on testicular function and can cause damage to multiple organ systems in the body. In animal cancer research, inhalation of EO can cause several tumorigenic changes, including leukemia, brain tumors, and breast tumors, while ingestion or subcutaneous injection of EO only forms tumors at the contact site.

2-chloroethanol (ECH) is a flammable liquid that irritates the body surface, has acute toxicity, and is rapidly absorbed through the skin at toxic doses. ECH has mild mutagenicity, potential for fetal toxicity and teratogenic changes, and can cause damage to several organ systems in the body, including the lungs, kidneys, central nervous system, and cardiovascular system. ECH showed negative results in animal cancer tests.

The ethylene oxide sterilization device is a key equipment for disposable sterile medical device manufacturing enterprises. Qualified masks must be produced in a sterile environment to achieve protective effects. Manufacturers generally choose to use ethylene oxide (EO) as a disinfectant in their workshops, which has strong penetration and can reach deep into the disinfected items, killing most pathogenic microorganisms, including bacterial spores, spores, viruses, and fungi.

ECH, as one of the degradation products of EO, may be generated and remain during the sterilization process of medical devices. ECH is also toxic to the human body, and its residual levels need to be strictly controlled to ensure the safety of medical devices.

Therefore, the national standard GB/T 14233.1-2022 specifies the limits of residual ethylene oxide (EO) and 2-chloroethanol (ECH).

Method principle:

The basic principle is to place the sample to be tested in a closed container, heat and raise the temperature to make the volatile components in the sample evaporate from the sample matrix, and reach equilibrium in the gas-liquid (or gas-solid) phase. Then, directly extract the gas from the top of the container for chromatographic analysis to test the composition and content of volatile components in the sample.

Experimental instruments:

Gas chromatograph: Shanghai Jinghe AnalyElf G60 GC System

Headspace sampler: AHS-900A (32-bit fully automatic headspace sampler)

Nitrogen: 40L steel cylinder gas (purity>99.999%)

Hydrogen generator: XGH-300

Air Generator: XGA-2000